I have recorded a test script for a hybrid app on Samsung S3. I now want to execute the same script on Samsung S2. The script execution is failing as both the devices have different screen sizes.
Does Ranorex support executing the same script on multiple devices with various screen sizes?

Yes, this should normally work as the elements are normally recognized using one of the unique attributes and not using relative coordinates.
Could it be that you are using absolute pixels as "Location" for your actions in the recording?
If so could change it to proportional?

Why do you assume that it has something to do with the size?
In order to analyze your issue in detail could you please send us the report or the error message?